U.S. patent number 10,005,102 [Application Number 14/551,855] was granted by the patent office on 2018-06-26 for coated mat of inorganic fibers, and functional decorative layers, manufactured therefrom, in floor, ceiling and wall coverings.
This patent grant is currently assigned to Johns Manville. The grantee listed for this patent is JOHNS MANVILLE. Invention is credited to Klaus Friedrich Gleich, Michael Ketzer, Simone Schneider.
United States Patent |
10,005,102 |
Ketzer , et al. |
June 26, 2018 |
Coated mat of inorganic fibers, and functional decorative layers,
manufactured therefrom, in floor, ceiling and wall coverings
Abstract
A method for manufacturing a mat of inorganic fibers including
the manufacture or supply of a mat of inorganic fibers having two
major surfaces, which is strengthened with a chemical binder, or by
means of a hydrodynamic method, coating of a first major surface of
the mat by means of the application of an aqueous solid dispersion
on one of the two sides of the mat, drying the coated mat, printing
the coated mat by means of rotary printing, digital printing,
screen printing, or offset printing on the first major surface of
the coating, optional application of a protective layer onto the
first major surface, application of a binder, at least partial
drying and at least partial crosslinking of the mat to which binder
has been applied, and rolling up of the obtained material web, or
cutting to size as sheets.
Inventors: |
Ketzer; Michael (Collenberg,
DE), Gleich; Klaus Friedrich (Highlands Ranch,
CO), Schneider; Simone (Lohr, DE) |
Applicant: |
Name |
City |
State |
Country |
Type |
JOHNS MANVILLE |
Denver |
CO |
US |
|
|
Assignee: |
Johns Manville (Denver,
CO)
|
Family
ID: |
52002738 |
Appl.
No.: |
14/551,855 |
Filed: |
November 24, 2014 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20150158765 A1 |
Jun 11, 2015 |
|
Foreign Application Priority Data
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|
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|
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Dec 5, 2013 [DE] |
|
|
10 2013 020 405 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B05D
7/50 (20130101); B05D 3/0254 (20130101); B05D
7/584 (20130101); D04H 1/4218 (20130101); C03C
25/10 (20130101); D06N 3/0022 (20130101); E04C
2/16 (20130101); B05D 2252/02 (20130101); D06N
2209/1657 (20130101); C03C 2217/72 (20130101); Y10T
428/24893 (20150115); B44C 1/24 (20130101); E04F
13/002 (20130101); B44C 5/04 (20130101); Y10T
428/24372 (20150115); Y10T 428/25 (20150115); D06N
2209/121 (20130101); Y10T 428/2481 (20150115) |
Current International
Class: |
B05D
3/02 (20060101); D04H 1/4218 (20120101); E04C
2/16 (20060101); C03C 25/10 (20180101); D06N
3/00 (20060101); B05D 7/00 (20060101); E04F
13/00 (20060101) |
Field of
Search: |
;427/394 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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10 2009 023737 |
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Dec 2010 |
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DE |
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2 644 762 |
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Oct 2013 |
|
EP |
|
2 672 001 |
|
Dec 2013 |
|
EP |
|
2 690 217 |
|
Jan 2014 |
|
EP |
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2 269 814 |
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Feb 2014 |
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EP |
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2008 101678 |
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Aug 2008 |
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WO |
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2008 101679 |
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Aug 2008 |
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WO |
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Primary Examiner: Fletcher, III; William P
Attorney, Agent or Firm: Touslee; Robert D.
Claims
The invention claimed is:
1. A method for the manufacture of mats of inorganic fibres, which
on one of two major surfaces have at least one printed coating
comprising the steps: (i) manufacture or supply of a mat of
inorganic fibres, the mat comprises two major surfaces, which is
strengthened with a chemical binder, or by means of a hydrodynamic
method, (ii) coating of one side of the mat by means of the
application of an aqueous solid dispersion on a first major surface
of the two major surfaces of the mat, (iii) drying of the coated
mat obtained in accordance with step (ii), (iv) printing of the
coated mat obtained in accordance with step (iii) by means of
rotary printing, digital printing, screen printing, or offset
printing on the first major surface of the coating, (v) optional
application of a protective layer onto the first major surface,
(vi) application of a binder, (vii) at least partial drying and at
least partial crosslinking of the mat to which binder has been
applied, (viii) rolling up of the obtained material web, or cutting
to size as sheets, characterised in that, (a) the mat manufactured
in step (iii) has a permeability to air (in accordance with Gurley)
in the range from 5 to 50 sec/100 ml, and smoothness values (in
accordance with Bekk) between 100 and 500 sec, (b) the aqueous
dispersion applied in step (ii) comprises particles with a grain
size in the range from 0.1 .mu.m to 5 .mu.m, (c) the aqueous
dispersion applied in step (ii) is applied using transfer coating
or slot bead coating, (d) the coating applied in step (iii) after
drying corresponds to a mass per unit surface area of between 50
and 200 g/m.sup.2, (e) the printing executed in step (iv) takes
place directly onto the surface coating obtained in accordance with
step (iii), (f) the binder in step (vi) is a binder system capable
of B-stage curing, and the binder system capable of B-stage curing
is transferred in step (vii) into a B-stage state, (g) the
application of the B-stage capable binder system in step (vi) takes
place on a second major surface of the two major surfaces of the
mat, or by impregnation of the mat, and (h) the quantity of the
B-stage capable binder system applied in step (vi) is between 40
and 80% by mass.
2. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of one or more of glass fibre
mats or mats of inorganic mineral and ceramic fibres.
3. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of mats based on mineral fibres,
in which the average length of the mineral fibres is between 5 and
120 mm.
4. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of mats based on mineral fibres,
in which the average fibre diameter is between 5 and 30 .mu.m.
5. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of mats based on mineral fibres
in which the mass per unit surface area is between 25 and 150
g/m.sup.2, wherein these numbers relate to a planar structure with
binder.
6. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of mats based on glass fibres,
in which the average length of the glass fibres is between 5 and
120 mm.
7. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of mats based on glass fibres,
in which the average fibre diameter is between 6 and 30 .mu.m.
8. The method according to claim 7, characterised in that, the mat
has less than 30% by mass of additional glass microfibres, relative
to the total content of inorganic fibres, or glass fibres; the
average diameter of the glass microfibres is between 0.1 and 6
.mu.m.
9. The method according to claim 1, characterised in that, the mat
of inorganic fibres takes the form of mats based on glass fibres in
which the mass per unit surface area is between 25 and 150
g/m.sup.2, wherein these numbers relate to a planar structure with
binder.
10. The method according to claim 1, characterised in that, the mat
has glass fibres and mineral fibres as the inorganic fibres,
wherein the mat can also have a layered structure of mineral fibres
and glass fibres.
11. The method according to claim 1, characterised in that, the mat
of inorganic fibres, in particular of glass fibres, has a
proportion of binder of between 5 and 30%, wherein these numbers
relate to the total mass of the mat with binder.
12. The method according to claim 1, characterised in that, the mat
of inorganic fibres, in particular mats of glass fibres, have a
permeability to air (a) in the range between 1,000 and 3,000
l/cm.sup.2sec, measured in accordance with DIN-EN9237, if the mat
has been strengthened in step (i) with a binder, or (b) values
between 1,200 and 4,000 l/cm.sup.2sec, if the mat has been
strengthened in step (i) by means of a hydrodynamic method.
13. The method according to claim 1, characterised in that, the
coating applied in step (ii) has a thickness of between 50 and
1,000 .mu.m, after the drying process in step (iii).
14. The method according to claim 1, characterised in that, the
coating applied in step (ii) is formed in two or more layers.
15. The method according to claim 1, characterised in that, the
drying process in step (vii) at least partially cures the binder
capable of B-stage curing, but not completely, such that a residual
moisture content of between 1% and 5%, remains in the binder
capable of B-stage curing.
16. The method according to claim 1, characterised in that, the
aqueous dispersion applied in step (ii) comprises particles with a
grain size in the range from 0.1 .mu.m to 5 .mu.m, and functional
materials in the form of particles being with the same size range,
said particulate functional materials being selected from the group
consisting of: materials for purposes of increasing fire resistance
(flame retardants), materials for purposes of dissipating
electrostatic charges, materials for purposes of screening
electromagnetic radiation, and organic or inorganic pigments
wherein the aforementioned aqueous dispersion consists of said
particles with a grain size in the range from 0.1 .mu.m to 5 .mu.m,
and functional material or mixtures of functional materials.
Description
BACKGROUND OF THE INVENTION
The invention relates to mats of inorganic fibres, in particular
glass mats, with a special coating and decorative coatings,
manufactured therefrom, in floor, ceiling and wall coverings, and
also a method for their manufacture.
Decorative coatings in the form of two-dimensional rolls or sheets
of material as mats based on thermoplastic fibres or cellulose
fibres with decorative printing and, on occasion, with additional
plastic finishes, are of sufficiently known art. Mat-form materials
with mineral fillers as plasterboard reinforcements, or so-called
decorator mats with mineral coatings, which after installation on
the wall require a further coating, are also of known art.
Decorative coatings inside buildings, in particular in public
and/or commercial buildings, must become ever safer with regard to
the risks that can be brought about by fires. The heightened fire
protection requirements are of known art from the legal regulations
of the experts, which are steadily intensifying. These heightened
requirements increasingly involve also individual components of
internal structures, such as, for example, floor coverings, wall
coverings and/or ceiling coatings. Such decorative elements, taken
on their own, can sometimes be classified as unsafe with regard to
the fire protection requirements, or else can be manufactured only
very expensively. However, by the use of glass mats, which have
decorative layers, the said fire protection requirements can be
fulfilled. Printed mats of inorganic fibres, in particular glass
mats, have calorimetric values of less than 5,000 J/kg, compared
with paper with values of more than 10,000 J/kg, and thus
automatically have an appropriate level of fire resistance. By this
means it is possible to manufacture wall, floor or ceiling
coverings in a very simple and safe manner.
The manufacture of printed mats of inorganic fibres, in particular
glass mats, is not trivial. The high level of permeability to air
of mats of inorganic fibres, in particular glass mats, leads to the
fact that conventional coatings, e.g. those based on calcium
carbonate and/or kaolin, fill the spaces between the fibres. This
leads to end products that have an undesirably high mass per unit
surface area of, for example, more than 260 g/m.sup.2, where the
basic mat has a figure of only 55 g/m.sup.2. Comparable papers have
in contrast a mass of approx. 70-80 g/m.sup.2 as end products.
Furthermore coatings or coating materials of known art lead to a
surface quality that is insufficient to fulfil the high
requirements of direct printing (e.g. rotary printing) or similar
printing methods. Faults in the surface quality, such as for
example unevennesses or micro-openings, lead to so-called missing
dots, i.e. very small points on the surface that after printing
have a lack of ink. The reason for this is that printing rollers
are unable to wet such low points in the surface with ink.
The object was therefore to provide mats with a coating, which mats
possess a very low total mass and a low permeability to air, and
have an excellent surface quality.
DETAILED DESCRIPTION OF THE INVENTION
The subject of the present invention is a method for the
manufacture of mats of inorganic fibres that have at least one
printed coating on one of the two surfaces, comprising the steps:
(i) manufacture or supply of a mat of inorganic fibres, which is
strengthened with a chemical binder, or by means of a hydrodynamic
method, (ii) coating of one side of the mat by means of the
application of an aqueous solid dispersion on one of the two sides
of the mat, (iii) drying of the coated mat obtained in accordance
with step (ii), (iv) printing of the coated mat obtained in
accordance with step (iii) by means of direct printing methods on
the surface of the coating, (v) optional application of a
protective layer onto the printed surface, (vi) application of a
binder, and removal of excess binder as necessary, (vii) at least
partial drying and at least partial crosslinking of the mat to
which binder has been applied, (viii) rolling up of the material
web obtained, or cutting to size as sheets, characterised in that
(a) the mat manufactured in step (iii) has a permeability to air
(in accordance with Gurley) in the range from 50 to 150 sec/300 ml,
preferably from 5 to 50 sec/100 ml, and smoothness values (in
accordance with Bekk) of 100-500 sec, and preferably between
150-400 sec, (b) the aqueous dispersion applied in step (ii)
comprises particles with a grain size in the range from 0.1 .mu.m
to 5 .mu.m, and preferably in the range from 0.5 .mu.m to 2 .mu.m,
(c) the aqueous dispersion applied in step (ii) is applied by means
of an application process not requiring the application of force,
(d) the coating applied in step (iii) after drying corresponds to a
mass per unit surface area of between 50 and 200 g/m.sup.2, and
preferably between 80 and 150 g/m.sup.2, (e) the printing executed
in step (iv) takes place directly onto the surface coating obtained
in accordance with step (iii), (f) the binder in step (vi) is a
binder system capable of B-stage curing, and the binder system
capable of B-stage curing is transferred in step (vi) into a
B-stage state, (g) the application of the binder system capable of
B-stage curing in step (vi) takes place onto the non-coated side of
the mat, or by impregnation of the mat, and (h) the quantity of
binder system capable of B-stage curing applied in step (vi) is
between 40 and 80% by mass, and preferably between 50 and 70% by
mass, wherein these numbers relate to the total mass of the mat
after it has been fully dried.
Further subjects of the present invention are the products and
intermediate products manufactured by means of the inventive
method. The inventive method can also be interrupted, i.e. steps
(i) to (iii) and steps (iv) to (vii) can be executed separately
from one another, both in time and space. The coated mat obtained
in accordance with step (iii) represents a valuable intermediate
product.
A further subject of the present invention is a mat of inorganic
fibres, which on one of the two surfaces has a printable coating,
wherein: (i) the coating comprises particles, whose grain size lies
in the range from 0.1 .mu.m to 5 .mu.m, and preferably between 0.5
.mu.m and 2 .mu.m, and the mass per unit surface area of the
coating corresponds to a mass per unit surface area of between 50
and 200 g/m.sup.2, and preferably between 80 and 150 g/m.sup.2,
(ii) the coating has been applied onto the mat by means of an
application process not requiring the application of force, (iii)
the printing can take place directly onto the surface coating,
characterised in that the coated mat has a permeability to air (in
accordance with Gurley) in the range from 50 to 150 sec/300 ml,
preferably from 5 to 50 sec/100 ml, and smoothness values (in
accordance with Bekk) of 100-500 sec, and preferably between
150-400 sec.
A further subject of the present invention is a mat of inorganic
fibres, which on one of the two surfaces has a printed coating,
wherein: (i) the coating comprises particles, whose grain size lies
in the range from 0.1 .mu.m to 5 .mu.m, and preferably between 0.5
.mu.m and 2 .mu.m, and the mass per unit surface area of the
coating corresponds to a mass per unit surface area of between 50
and 200 g/m.sup.2, and preferably between 80 and 150 g/m.sup.2,
(ii) the coating has been applied onto the mat by means of an
application process not requiring the application of force, (iii)
the printing has taken place directly onto the surface coating,
(iv) the coated and printed mat has a binder system capable of
B-stage curing in the B-stage state, (v) the quantity of the binder
system capable of B-stage curing is between 40 and 80% by mass, and
preferably between 50 and 70% by mass, wherein these numbers relate
to the total mass of the mat after it has been fully dried.
The inventively coated mats of inorganic fibres can have still
further functional layers, for example antibacterial, antistatic,
fire resistant and/or conductive layers.
The inventively coated mats of inorganic fibres, in particular the
glass mats, have a mass per unit surface area of between 50 and 500
g/m.sup.2, and preferably of between 100 and 500 g/m.sup.2, wherein
these numbers relate to the end product, wherein the coating
amounts to at least 25 g/m.sup.2, and a maximum of 300
g/m.sup.2.
The inventively coated mats of inorganic fibres, in particular the
glass mats, have a permeability to air (in accordance with Gurley)
in the range from 50 to 150 sec/300 ml, preferably from 5 to 50
sec/100 ml, more preferred from 10 to 30 sec/100 ml.
The inventively coated mats of inorganic fibres, and in particular
the glass mats, have a very smooth surface quality, which,
expressed as a roughness or smoothness, have a smoothness value
(Bekk) of between 100 and 500, and preferably of between 150 and
400.
Surfaces of such quality can be printed directly with printing
technologies of known art, such as digital printing, rotary
printing, or screen printing. In the context of the invention,
"directly" signifies that the surfaces no longer need to be
smoothed using abrasive methods, and there are no longer any
unevennesses present that must be removed by the application of
appropriate fillers.
Mats of Inorganic Fibres
The mats of inorganic fibres take the form of glass fibre mats,
and/or mats of inorganic mineral and ceramic fibres.
Suitable inorganic mineral and ceramic fibres include
aluminosilicate-, ceramic-, dolomite-wollastonite fibres, or fibres
of vulcanites, preferably basalt-, diabase- and/or melaphyre
fibres, and in particular basalt fibres. Diabase and melaphyre are
together summarised as palaeo-basalts and diabase is often also
denoted as greenstone.
Mats based on mineral fibres can be formed from filaments, i.e.
continuous long fibres, or from staple fibres. The average length
of the staple fibres in the inventively used mat of mineral fibres
is between 5 and 120 mm, preferably between 5 and 90 mm, and in
particular between 5 and 20 mm. In a further form of embodiment of
the invention the mineral fibre mat contains a mixture of
continuous fibres and staple fibres. Mineral fibre mats of staple
fibres of the above-cited average length are preferred. The average
fibre diameter of the mineral fibres is between 5 and 30 .mu.m,
preferably between 8 and 18 .mu.m, and particularly preferably
between 8 and 10 .mu.m.
The mass per unit surface area of the mat of mineral fibres is
between 25 and 150 g/m.sup.2, and preferably between 30 and 70
g/m.sup.2, wherein these numbers relate to a planar structure with
binder.
Mats based on mineral fibres can be formed from filaments, i.e.
continuous long fibres, or from staple fibres. The average length
of the staple fibres is between 5 and 120 mm, preferably between 10
and 90 mm, and in particular between 5 and 20 mm. In a further form
of embodiment of the invention the mineral fibre mat contains a
mixture of continuous fibres and staple fibres. Mineral fibre mats
of staple fibres of the above-cited average length are preferred.
The average fibre diameter of the mineral fibres is between 6 and
30 .mu.m, preferably between 8 and 18 .mu.m, and particularly
preferably between 8 and 10 .mu.m.
In addition to the above-cited diameters, so-called glass
microfibres can also find application. The preferred average
diameter of the glass microfibres is here between 0.1 and 6 .mu.m,
and preferably between 0.8 and 3.5 .mu.m. The proportion of glass
microfibres is less than 30% by mass related to the total content
of inorganic fibres, or glass fibres. The microfibres forming the
textile surface can also be present in mixtures with other fibres,
preferably glass fibres. Moreover a layered structure of
microfibres and glass fibres is also possible.
The mass per unit surface area of the mat of glass fibres is
between 25 and 150 g/m.sup.2, and preferably between 30 and 70
g/m.sup.2, wherein these numbers relate to a planar structure with
binder. Suitable glass fibres include in particular those that have
been manufactured from A-glass, E-glass, S-glass, C-glass, T-glass
or R-glass; particularly preferred are fibres of C-, E-, T-glass,
and mineral fibres based on basalt.
The mats can be manufactured in accordance with any method of known
art. In the case of glass mats this is preferably the dry- or
wet-laying method.
The binder proportion of the mat of inorganic fibres, in particular
of the glass mat, is between 5 and 30%, and preferably between 10
and 25%, wherein these numbers relate to the total mass of the mat
with binder.
The inventively used mats of inorganic fibres, in particular the
glass mats, can also include reinforcements. Reinforcements serve
to improve the mechanical properties of the mats, in particular the
longitudinal and transverse strengths. Possible reinforcements
include longitudinal threads or lattice structures. Suitable
reinforcement materials are glass threads or structures of high
modulus materials; these are introduced onto or into the planar
textile structure during manufacture.
The inventively used mats of inorganic fibres, in particular mats
of glass fibres, have a permeability to air in the range between
1,000 and 3,000 l/cm.sup.2sec, measured in accordance with
DIN-EN9237, if the mat has been strengthened in step (i) with a
binder, and values between 1,200 and 4,000 cm.sup.2sec, if the mat
has been strengthened in step (i) by means of a hydrodynamic
method. Mats with higher air permeabilities have a tendency to fill
during coating with a coating material, as a result of which the
masses per unit area of the coated mats increase excessively. Mats
with air permeabilities that are too low have a tendency to allow
only insufficient impregnation values in a subsequent impregnation
of the coated mat.
In addition to adaptation of the permeability to air, the
permeability of the mat of inorganic fibres can also--alternatively
or additionally--be optimised by means of hydrophobisation of the
fibre surface. This is possible, for example, by the addition of a
hydrophobisation agent to the binder. A suitable hydrophobisation
agent is, for example, "Nuva 2155", which can be obtained from the
Clariant company.
The mats used for purposes of coating have a minimum strength of 20
N/5 cm.
The measurement is undertaken in accordance with EN29073, Part 3 on
samples with a width of 5 cm wide and a clamping length of 200 mm.
Here the numerical value of the preload force, specified in
centi-newtons, corresponds to the numerical value of the mass per
unit surface area of the sample, specified in grams per square
meter.
Binder
The inventive mats of inorganic fibres, in particular the glass
mats, are preferably pre-strengthened and for this purpose
preferably contain urea binder, melamine binder, acetate binder,
acrylate binder, or mixtures of the above-cited binders. In a
further preferred configuration the mat contains binder based on
polyvinyl alcohols. Moreover binders that are free of formaldehyde
are particularly preferred.
The proportion of binder in the mat of inorganic fibres, in
particular the glass mat, is between 5 and 30%, and preferably
between 10 and 25%, wherein these numbers relate to the total mass
of the mat with binder, but without a coating.
The binder can in addition also have fillers, in particular
inorganic fillers, and particularly preferably inorganic mineral
fillers, wherein the proportion of these is between 5 and 30%, and
preferably between 10 and 20%, wherein these numbers relate to the
total mass of the mat with binder, but without a coating.
Coating
The inventive mats of inorganic fibres, in particular the glass
mats, have a coating of at least one layer on one of their two
surfaces. Furthermore the coating can also be designed to have more
than one layer, i.e. two, three, or more than three, layers. One-
and two-layer coatings, in particular one-layer coatings, are
preferred.
The coating that is applied onto the surface of the mat contains
defined particle sizes, and is especially suitable for the direct
application of decorative layers by means of direct printing
techniques. The coating is selected such that it does not penetrate
and fill the mat completely, as a result of which a low mass per
unit surface area of the coating, i.e. of the coated mat, is made
possible, while having the mentioned permeability to air (in
accordance with Gurley) in the range from 50 to 150 sec/300 ml,
preferably from 5 to 50 sec/100 ml, more preferred from 10 to 30
sec/100 ml. The coating makes possible a very smooth surface,
which, expressed in terms of Bekk values, lies in the range between
100 and 500 sec, and preferably between 150 and 400 sec. In
addition the coating has a very low void density. As a result no
printing voids ensue in the direct printing process. This
particular surface quality, i.e. a combination of low roughness and
low numbers of voids, is achieved in particular by the use of
application methods not requiring the application of force.
The inventively coated mats have a permeability to air (Gurley) of
between 50 and 150 sec/300 ml, preferably from 5 to 50 sec/100 ml,
more preferred from 10 to 30 sec/100 ml, and a smoothness in
accordance with Bekk of between 100 and 500 sec. For purposes of
ensuring the desired printability of the coating and the use of the
printed mats the maintenance of both ranges of values is of crucial
significance. In addition to the roughness of the surface, which is
important for the print quality, the permeability to air also plays
an important role in the impregnation of the mats.
The requirements for an extremely smooth surface that can be
directly printed on can only be satisfied with great difficulty on
mats based on inorganic fibres, in particular glass fibre mats,
using conventional coating methods. Either the surface is good, but
the adhesion to the substrate is poor, or the adhesion to the
substrate is good, but, as a result of the capillary effects of the
substrate, defects occur, such as e.g. pinholes. The avoidance of
the penetration of the coating material into the mat requires
moreover suitable coating materials and a coating method that
applies the coating material onto the mat surface not requiring the
application of force, and thereby at the same time enables
sufficient adhesion to the mat. The following coating that has been
discovered enables such a coating onto the mats of inorganic fibres
as cited.
The inventive coating comprises particles, whose size lies between
0.1 and 5 .mu.m, i.e. the D50 value, or median value, and
particularly preferably the D100 value, or median value, lies in
the above-cited range. The particle size preferably lies between
0.5 and 2 .mu.m. Particle sizes of less than 0.5 .mu.m densify the
surface such that a later introduction of binder is only possible
with extreme dilution, which leads to technical problems in the
process.
The coating can also comprise mixtures of various types and sizes
of particles, wherein the respective D50/D100 values, i.e. median
values, in each case, both alone and also taken together, lie in
the above-defined range.
Suitable particles are inorganic particles or pigments, in
particular white pigments. Here these preferably take the form of
barium sulphate, calcium carbonate, calciumsulfoaluminate, kaolin,
talcum, titanium dioxide, zinc oxide, diatomaceous earth,
SiO.sub.2, chalk, coating clay, calcined clay, colour pigments,
silicates, or mixtures of the same. The inventive particles are
selected from materials that fulfil the criteria for A2 or SBI B S1
D0 in the later fire test. The coating particularly preferably
contains at least 5% by mass, and preferably at least 10% by mass,
of titanium dioxide.
In addition the coating can also have functional materials in the
form of particles. The functional materials in the form of
particles that may, on occasion, be present, usually have the same
particle size as the other particles. The functional materials
preferably take the form of materials for purposes of increasing
fire resistance (flame retardants), materials for purposes of
dissipating electrostatic charges, materials for purposes of
screening electromagnetic radiation, and organic or inorganic
pigments, in particular colour pigments.
Flame retardants take the form of inorganic flame retardants,
organophosphorus flame retardants, nitrogen-based flame retardants
or intumescent flame retardants. Halogenated (brominated and
chlorinated) flame retardants can also be used, but are less
preferred as a result of their risk assessment. Examples of such
halogenated flame retardants are polybrominated diphenyl ether,
e.g. DecaBDE, tetrabrombisphenol A, and HBCD
(hexabromocyclododecane).
Nitrogen-based flame retardants take the form of melamines and
ureas.
The organophosphorus flame retardants typically take the form of
aromatic and alkyl esters of phosphoric acid. TCEP (tris
chloroethyl phosphate), TCPP (tris chloropropyl phosphate), TDCPP
(tris(dichloroisopropyl) phosphate), triphenyl phosphate, trioctyl
phosphate (tris(2-ethylhexyl) phosphate), are preferably used.
The inorganic flame retardants typically take the form of
hydroxides, such as aluminium hydroxide and magnesium hydroxide,
borates, such as zinc borate, ammonium compounds, such as ammonium
sulphate, red phosphorus, and antimony oxides, such as antimony
trioxide and antimony pentoxide, or vermiculite.
By the use of agents for purposes of increasing the electrical
conductivity antistatic and electromagnetic screening effects can
be achieved.
The antistatic agents commonly take the form of particles that are
electrically conductive. Suitable materials are electrically
conductive carbon materials such as carbon black, graphite and
carbon nanotubes (C-nanotubes), or conductive plastics.
The materials for purposes of screening electromagnetic radiation
commonly take the form of electrically conductive materials.
The coating can in addition also have binding agents, which after
the drying process remain in the coating. These additional binding
agents are preferably added in quantities of 1 to 50 parts by mass,
and particularly preferably 5 to 25 parts by mass of binding agent,
relative to 100 parts by mass of inorganic pigment. Amongst the
additional binding agents so-called emulsion polymers based on PVC,
polystyrene acetate, polyacrylate acetate, and polyvinyl acetate,
also in each case in the form of copolymers, are preferred.
Furthermore the coating can also have one or a plurality of
thickeners. These preferably take the form of synthetic polymers,
in particular celluloses, preferably carboxymethylcellulose.
Furthermore the coating can also comprise additional fluorescent or
phosphorescent colourants, in particular visual whiteners. Further
components of the coating can also be flow aids, or other
colourants.
The coating (total thickness of the coating) is between 50 and
1,000 .mu.m, and preferably between 100 and 500 .mu.m after
drying.
Insofar as the aqueous dispersion that is used for purposes of
coating in addition also has binding agents, the application can
also take place in a two-layer form, or on occasion in a
multi-layer form. Here a first layer is firstly applied onto the
coating material and dried to the extent that it no longer
automatically penetrates into the mat. Following on immediately, or
also at a later point in time, a further aqueous dispersion can be
applied and the required surface quality can be generated. In this
form of embodiment the coating materials for the first and second
layers of the coating can be the same or different.
The second, i.e. outer, layer of the coating preferably has a mass
per unit surface area of between 10% and 40%, and preferably
between 10% and 20%, of the total mass per unit surface area of the
coating layers.
The coating material is applied in the form of an aqueous
dispersion by means of an application process not requiring the
application of force. Such processes ensure that the coating
material cannot penetrate into the mat as a result of external
mechanical forces. All methods of known art are suitable for this
purpose, in particular, however, the transfer coating method and
the slot bead method. In the transfer coating method the coating
material is firstly applied onto a transfer medium, for example a
tape, paper or film with release properties, and the mat of
inorganic fibres is laid onto the transfer medium with the coating
material and is pressed on with a light pressure, i.e. a pressure
that is slightly above the ambient pressure, and in this manner the
adhesion of the coating material to the surface of the mat is
ensured. In the slot bead method the coating material is applied
onto the mat without the application of force by means of a broad
slot. Here the application takes place in a mass-controlled
manner.
The inventive coatings, in particular the particles, only penetrate
partially into the mat. By virtue of the particle sizes selected,
together with the surface quality, a coating with too high a
roughness can be prevented, and the formation of a so-called
"orange peel" effect can be avoided.
The drying of the inventive coating is undertaken in the usual
temperature ranges.
Printing
In step (iv) the printing is executed directly onto the surface
coating, For this purpose ink is applied to the coated mats and a
decorative pattern is generated. Suitable printing methods are, in
particular, rotary printing, digital printing, screen printing,
offset printing, etc.
In the context of the invention, "directly" signifies that the
surfaces no longer need to be smoothed using abrasive methods, and
there are no longer any unevennesses present that must be removed
by the application of appropriate fillers.
In a further step in the production process the printed mats are
then impregnated with a B-stage binder system.
Protective Layer
In step (v) the printed surface of the coating can optionally be
provided with a protective layer. Here all transparent varnishes,
or materials similar to varnish that are compatible with the
coating, are suitable. Here UV-resistant and/or UV-protective
varnishes, or layers similar to varnish, are particularly
preferred.
B-stage Binder System
In step (vi) the printed mat is furnished with a binder system
capable of B-stage curing.
The inventively used binder system capable of B-stage curing
comprises (i) at least one binder capable of B-stage curing, and,
on occasion, at least one further, self-crosslinking, preferably
thermally crosslinking, binder.
The quantity of binder system capable of B-stage curing applied in
step (vi) is between 40 and 80% by mass, and preferably between 50
and 70% by mass, wherein these numbers relate to the total mass of
the mat after the binder has been fully dried and crosslinked.
"Binders capable of B-stage curing" are understood to be binders
that are only partially strengthened, i.e. cured, i.e. are present
in the B-stage state, and can still experience a final
strengthening, for example by means of later thermal treatment.
Such B-stage binders are described in detail in U.S. Pat. No.
5,837,620, U.S. Pat. No. 6,303,207 and U.S. Pat. No. 6,331,339. The
B-stage binders there disclosed are also the subject of the present
description. B-stage binders preferably take the form of binders
based on furfuryl alcohol formaldehyde resins, phenol formaldehyde
resins, melamine formaldehyde resins, urea formaldehyde resins, and
mixtures of these. They preferably take the form of aqueous
systems. Other preferred binder systems are binders that are free
of formaldehyde. B-stage binders are distinguished by the fact that
they can be subjected to a multistage curing process, i.e. after
the first curing, or the first curings, they still have a
sufficient binding action (in the B-stage state) so as to be able
to use this in the further processing. Usually such binders are
cured in one step at temperatures of approximately 350.degree. F.
after the addition of a catalyst.
For purposes of forming the B-stage such binders are cured, if
necessary after the addition of a catalyst. The curing catalyst
proportion is up to 10% by mass, and preferably 0.1 to 5% by mass
(related to the total binder content). Ammonium nitrate, and
organic aromatic acids, e.g. maleic acid and p-toluene sulphonic
acid, are, for example, suitable as the curing catalyst, since
these allow the B-stage state to be achieved more quickly. In
addition to ammonium nitrate, maleic acid and p-toluene sulphonic
acid, all materials that have a comparable acidic function are
suitable as curing catalysts. To achieve the B-stage the planar
textile structure, impregnated with the binder, is dried under the
influence of temperature, without generating a complete cure. The
process parameters required are dependent on the binder system that
is selected.
The lower temperature limit can be influenced by the choice of
process duration, or by the addition of more or stronger acidic
curing catalysts.
Particularly preferred are B-stage binders based on urea
formaldehyde (UF), melamine formaldehyde (MF), epoxy, or mixtures
of UF and MF binders.
Self-crosslinking binders are binders that react chemically
completely, without the addition of a catalyst. The crosslinking is
preferably thermally induced. In particular it has been shown that
aqueous acrylate dispersions, polymer dispersions of vinyl acetate
and ethyls, or similar crosslinking binders, in particular
thermally crosslinking binders, are suitable. Particularly suitable
are acrylate binders.
The proportion of the self-crosslinking binder in the binder system
capable of B-stage curing is a maximum of 20% by mass, and
preferably a maximum of 15% by mass, and particularly preferably a
maximum of 10% by mass, wherein the values are with reference to
the binder system capable of B-stage curing (B-stage binders and
self-crosslinking binders), without taking into account the
residual moisture content, i.e. after drying and complete
crosslinking of the binder.
The proportion of the self-crosslinking binder in the binder system
capable of B-stage curing is preferably at least 2% by mass, and
preferably at least 5% by mass, wherein the values are with
reference to the binder system capable of B-stage curing (B-stage
binders and self-crosslinking binders), without taking into account
the residual moisture content, i.e. after drying and complete
crosslinking of the binder.
The application of the binder system capable of B-stage curing can
take place with the aid of methods of known art. In addition to
being sprayed on, impregnated, or pressed in, the binder can also
be applied by means of a coating process, or by means of rotating
nozzle heads. Furthermore a foam application is also possible. A
single-sided binder application, i.e. the application of the binder
only on the non-coated side of the mat, is also possible, and is in
particular necessary in the case of coated mats in which the
coating has been provided with an additional protective layer.
The drying process in step (vii) takes place at temperatures
between 90.degree. C. and a maximum of 200.degree. C., wherein the
dwell time in the dryer is typically between 30 and 60 seconds at
the above-cited range of temperatures. The drying process in
accordance with step (vii) causes the binder capable of B-stage
curing to be at least partially cured, but not completely, and the
additional, self-crosslinking binder to be completely cured.
The degree of curing of the B-stage binder is usually determined by
measuring the condensation moisture content occurring when curing
is complete.
The residual moisture content is determined as a relative
alteration in the mass of a sample when subjected to a temperature
of 170.degree. C. for 2 minutes. Complete curing leads to residual
moisture contents of less than 1%. Incompletely crosslinked
binders, i.e. binders in the B-stage, result in residual moisture
contents of between 1% and 5%, and preferably of between 1.5% and
4%, in inventively manufactured mats.
Alternatively it is possible to determine the degree of curing with
the aid of the tensile strength of the mat. Complete curing of the
binder system capable of B-stage curing is assumed to have occurred
if the tensile strength is a minimum of 95% or more of the maximum
possible tensile strength. The drying process in step (vii) causes
the B-stage binder to be not yet completely crosslinked, and the
mat to have a tensile strength of less than 20% of the maximum
possible tensile strength (in accordance with DIN EN 29073T3).
Drying devices of known art are used for the drying process.
The material webs are then rolled up and/or cut to size.
Use
The inventively coated and printed mats of inorganic fibres, in
particular the glass mats, are smooth, plane and light in mass. In
particular, very good values in terms of flammability also ensue
when compared with those for papers, i.e. the calorimetric values
of such coated mat-form materials make many applications possible,
for which other systems are not suitable.
The inventively coated mats of inorganic fibres, in particular the
glass mats, have a binder system capable of B-stage curing that is
still in the B-stage state (with residual moisture contents of
between 1% and 5%, and preferably of between 1.5% and 4%) and can
be laminated onto a substrate, or pressure can be applied to form a
laminate, for purposes of further processing under pressure and
temperature. Such composite materials are also the subject of the
present invention. Alternatively the application of pressure can
also be executed with two overlay papers or overlay mat-form
materials, which have a further B-stage binder. Here the decorative
mat-form material lies in the centre of the two overlay systems.
Suitable presses are e.g. short-cycle presses, continuous presses,
or similar methods of known art. Instead of the first overlay layer
an acrylic topcoat or a PU topcoat can also be separately applied
as an alternative. The use of short-cycle presses enables the use
of engraved press plates, which in turn allows a 3-D structure to
be formed on the substrate. The engraving can be configured such
that it is synchronised with the decorative pattern.
Pressure can also be applied to the inventively coated and printed
mats using the CPL/HPL method, if necessary with a backing paper on
the rear side. The plastic laminate can then be adhesively bonded
onto the material in a separate step. If necessary the HPL or CPL
method can also include an overlay paper.
The inventively coated and printed mats of inorganic fibres, in
particular the glass mats, can also be used for floor coverings,
e.g. PVC, cushion vinyl, or similar.
The inventively coated and printed mats of inorganic fibres, in
particular the glass mats, can be provided with a decorative
pattern and used as a wallcovering, e.g. as wallpaper. Such
decorative layers can conventionally be installed using paste on
conventional walls. If necessary such decorative layers are also
furnished in a "pre-glued" form, so as to enable simpler
installation on the wall.
Using calendaring machines, hot presses or double belt presses the
inventively coated and printed mats of inorganic fibres, in
particular the glass mats, can be applied onto thermoplastic
substrates such as PU, PVC, and PO.
Depending upon the final application still more additional
protective layers can be applied.
Alternatively other substrates such as glass wool sheets, cork
sheets, gypsum sheets, etc., can also be decorated. For floor
coverings anti-slip particles, e.g. of corundum, can also be
introduced.
In contrast to papers the inventively used mats of inorganic
fibres, in particular the glass mats, have a significantly higher
dimensional stability.
By the use of an additional binder in the coating process the
inventively coated and printed mats of inorganic fibres, in
particular the glass mats, have a surprisingly good, that is to say
excellent, drapability, and are not brittle in the same way as e.g.
conventional glass mats. For this reason the inventively coated and
printed mats of inorganic fibres, in particular the glass mats, are
also suitable for elastic flooring applications such as e.g.
cushion vinyl, or polyolefins, or polyurethane (PU), and also for
decorative ceiling panels of wooden boards, engineered wood sheets,
or mineral fibres, or plastic panels.
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